Method and apparatus for conditioning tobacco



METHOD AND APPARATUS FOR CONDITIONING TOBACCO Filed Feb. 6, 1964 July 26, 1966 F. H. LINDSTROM 3 Sheets-Sheet 1 INVENTOR July 26, 1966 F. H. LINDSTROM 3,262,458

METHOD AND APPARATUS FOR CONDITIONING TOBACCO Filed Feb. 6. 1964 5 Sheets-Sheet 2 INVENTOR.

FRED H Ll/VDSTROM July 26, 1956 F. H. LINDSTROM 3,262,458

METHOD AND APPARATUS FOR CONDITIONING TOBACCO 5 Sheets-Sheet 5 Filed Feb. 6, 1964 6 5:; ow 2 m m F 205525 m 7 I9: 252. w Tzfimm 226 1 mm r L 7 wwmmsmm sod J -2 -o. -m o United States Patent 3,262,458 7 METHOD AND APPARATUS FOR CONDITIONING TOBACCQ Fred H. Lindstrom, Homewood, Ill., assignor to Vacudyne Corporation, Chicago Heights, Ill., a corporation of Illinois Filed Feb. 6, 1964, Ser. No. 342,993 17 Claims. (Cl. 131-133) This invention relates to an improved method for conditioning and adjusting the moisture content of bulk products such as leaf tobacco which have been stored or confined in hogsheads, bales, or in similar confining units. More particularly the invention is directed to an improved process for humidifying or moisturizing materials under controlled and direction-oriented cycling conditions of vacuum and steaming. In a preferred embodiment, the invention finds utility in the conditioning and moistening of domestic and foreign types of green, semi-dried or redried tobacco to prepare the leaves for further processing. Also included within the scope of the invention is the apparatus for carrying out the process steps of the invention.

Many different types of processes for the conditioning and moisturizing of tobacco are known in the prior art. However, in each of these processes one or more objectionable features limits or impairs the general usefulness. In some instances the methods employed in the treatment cause excessive powdering or flaking and incident high ratios of scrap product to useful product. Other techniques require excessive processing times, tying up equipment and increasing over-all handling costs. Vacuum techniques of various types have been used. In still other cases pressurized systems have been employed. In some procedures the tightly packed or compressed leaf material has been subjected to contact with steam, water or moist air at the exterior bounding surfaces. In varied techniques, pipes or probes have been driven into the bales and water, steam or moist air introduced into the interior of the mass. In each of these and in the other prior art techniques the persistence of cold spots due to irregular vapor-penetration, failure to remove air or other non-condensible gases, and to the propensity to channeling have impaired the general effectiveness of the processes. been the inevitable result.

It is the aim of the present invention to provide a process which obviates the objectional features of prior art methods and techniques.

It is a principal object of the invention to provide an improved process for moistening materials under cycling conditions of vacuum and steaming and utilizing the principle of reverse flow. 7

Another object of the invention is to provide an improved treatment cycle for conditioning tobacco and related products whereby excessive waste is eliminated and a uniformly treated product is obtained;

Still another object of the invention is to provide an improved cycling process in which novel flow reversals through the material being treated promote gentle physical agitation of the bulk product and pulsing within the mass to provide a plurality of varied and random steam paths through the treated material.

A related object of the invention is to provide a tobacco treating process whereby the leaf product is fluffed and loosened during the physical introduction of con- 7 trolled moisture.

Uneven and incomplete moisturizing have 3,262,458 Patented July 26, 1966 ice a preferred form of the apparatus used in carrying out the method of the invention;

FIGURE 2 is a front elevational view of the probe drive assembly of the invention;

FIGURE 3 is a side view of the probe assembly;

FIGURE 4 is a cross-sectional view taken on the lines 4-4 of FIGURE 2;

FIGURE 5 is a graphic diagram of flow cycles embodying the teachings of the present invention; and

FIGURE 6 is a fragmentary cross-sectional view showing a structure for sealing the probe port.

Referring more particularly to the drawings, and especially to FIGURES 1, 2, 3 and 4 there is shown, for the purpose of illustrative disclosure, a preferred embodiment of the apparatus used in carrying out the invention. In the preferred arrangement depicted, the equipment illustrated comprises a treating or conditioning chamber 11, which is preferably an all steel rectangular or cylindrical shaped vacuum vessel, provided with a suitable sealing door 12. In the particular example illustrated, the chamber is a 2-hogshead unit, the hogsheads 13 being loaded into the chamber 11 on wheeled platform trucks 14 riding on a trackway 16 extending into the conditioning chamber 11. Vertically positionable probes 18 extend through packing glands 20 connected through the top wall 21 of the chamber 11. Probe drive units 30 (FIGURES 2, 3 and 4) are used to insert or force the probes 18 into the tobacco 25 packed in the hogsheads 13. The probes 18 themselves are provided with sharply tapered ends or points 37 to facilitate insertion into the tightly packed contents of the hogsheads. Longitudinal bores 38 extend axially throughout substantially the full length of the probes and transverse radial bores 40 communicate with the longitudinal bores 38 to provide steam flow paths and evacuation channels or ducts.

The ends 42 of the probes 18 extending or protruding outwardly or externally of the chamber 11 are coupled to high-vacuum type flexible hoses 44 connected to a conduit or line 45 adapted to serve as both a steam supply lead and a vacuum lead during the reversing flow cycling process. A steam supply source (not shown) is connected to the probe units 18 through a lead line 46, a leg 47, a pressure reducing valve 48, a low pressure steam accumulator and a shut-off valve 52, and line 45 to the flexible hose 44 through a pipe-to-hose coupling 53 and a hose-to-pipe fitting 54. The steam supply line 46 is branched to provide a leg 56 leading into the conditioning chamber through a conventional shut-off valve 57. In the arrangement illustrated the line 45 connected :to the flexible lead 44 of the probe 18 leads to an ejector of a steam evacuation system, through a shut-off valve 58. An auxiliary pipe line 311 connected between the shut-off valves 52 and 58 leading to another jet suction stage, through a shut-off valve 33, provides means for evacuation of air and other non-condensible gases through the probe system.

In the particular arrangement illustrated the over-all evacuation system includes a tank or condenser 59, a first stage ejector 60 connected between the conditioning chamber 11 and the condenser 59, and between the probes 18 and the condenser 59, and a second stage ejector 62 connected to both the probes 18 and the chamber 11. The second stage ejector 62 is also connected to the condenser 59 through an isolation valve 64, and the discharge from the second stage ejector 62 is controlled by a three-way valve 65 permitting recirculation of the efiluent steam to the conditioning chamber 11 through a lead line 66. The condenser 59 is provided with a cooling water supply line represented as a water pipe 67 extending into the condenser and delivering water serving as steam condensation means. A conventional shut-off valve 69 controls the flow of cooling water into the condensation tank 59. The condenser is preferably of a barometric type and is provided with suitable baffles, piping, etc. (not shown) and a barometric leg or vertical pipe 70 connected adjacent its lower end to a water pump 71. The pump 71 may be of a standard centrifugal type to remove water from the condenser and to ensure adequate water flow velocity. The efiiuent of the water pump may be discharged to waste or may be directed to a cooling tower (not shown) for ultimate recirculation.

As illustrated schematically in FIGURE 1, the first stage ejector 60 of the evacuation system is connected for evacuation of the conditioning chamber 11 through a suitable pipe or duct connection 73 and for evacuation of the probe lines through pipe 31. A line 74 leading from a steam source (not shown), and provided with a shutoff valve 76, in accordance with accepted and conventional practices, discharges motive steam into the first stage ejector 60 to provide the aspirating or pumping effect in a manner well-known in the art.

The second stage ejector 62 is connected to the conditioning chamber 11 through the probes 18 by a path including pipes 78 and 80, the shut-off valve 58 and lines 45 and 44. Thus the shut-off valve 58 serves to isolate the probes 18 and the second stage steam evacuation system. A steam supply source (not shown) is connected to feed motive steam into the second stage ejector 62 through a lead 84 and a suitable control valve 86.

It is apparent from the above detailed description of the structure illustrated that both the chamber 11 and the probes 18 are provided with steam supplies as well as with vacuum connections. The purpose of this arrangement will be apparent from a consideration of the following description of the preferred processing methods and the cycling operations of the invention. However, before considering the methods of the invention, the mechanism by which the probes 18 are lowered and retracted will be described.

It has previously been pointed out that the probes "18 are vertically positionable to move through glands 20 in the chamber wall from an elevated position in which the probes are above the tobacco contained in the hogshead 13 to a lowered, functional position in which the probes 18 extending into the tobacco for evacuation and for steam introduction. Referring now to FIGURES 2, 3 and 4, there is shown, for purposes of illustrative disclosure, a preferred structure for a probe drive unit 30 by which the probes 18 are selectively positioned. Mounted above the evacuation and steaming chamber 11 is a yoke 90 which is shaped generally in the form of an inverted U constructed of channel irons to define a pair of vertically extending, facing, and inwardly opening channels on guideways 92 and 93 surmounted by a bridging channel member or bar 95. The lower ends of the vertically extending channels or guides 92 and 93 are connected to a base plate 97 which is in turn fastened to a mounting plate 99 welded to the top wall 21 of the chamber 11.

A gear motor 101 is supported from one of the lateral channels 92 by means of a bracket 103, and a sprocket 105 mounted on the drive shaft 107 of the motor is coupled through a chain 108 to a driven sprocket 110 secured onto a vertically extending propelling shaft 112 rotatably mounted in end bearings .114 and 115 fastened to the bridging channel 95 and to the base plate 97 at opposed ends of the probe driving unit 30. The propelling shaft 112 is provided with external threads 117 extending along its length. A cross-head or probe clamp 119 provided with a cooperating threaded sleeve 1 21 is fastened onto the threaded shaft 112 so that the sleeve engages and travels along the shaft as the shaft rotates. Extending longitudinally from opposite ends of the cross-head are stub shafts 122 and 123 which extend into the opposed facing channels 92 and 93 and carry rollers or guides 124 and 125 journaled on the shafts. The rollers ride within the guideways defined by the channels 92 and 93. The

probe 18 is rigidly and firmly fastened adjacent its upper end into a clamp integral with the cross-head 119 whereby the probe 18 is moved upward or downward with the screw-driven cross-head as the motor-driven threaded shaft 112 is rotated. As shown in FIGURE 1, the free end of the probe 18 extends through the packing gland 20 in the top wall 21 of the vacuum chamber 11. In an alternative arrangement probes may be inserted into the hogsheads or bales prior to placing the hogsheads in the evacuation or conditioning chamber. The exposed ends of the probes are then coupled to hoses or pipes for vacuum and for steam treatment of the material contained in the hogsheads or bales.

For the purpose of illustrative disclosure, and not by way of limitation, a preferred processing and conditioning cycle is depicted schematically in FIGURE 5. The probe lines and sealed chamber containing one or more hogsheads of tobacco to be treated are subjected to an initial evacuation by means of the second stage steam ejector 62 (FIGURE 1) to remove most of the gas from the chamber. The first stage ejector is then actuated to achieve a final pressure of about 0.2 inch of mercury (C) absolute. In the cycle illustrated, the initial high evacuation requires about 7 minutes. Moisturizing steam is then introduced into the chamber (through line 56 or line 66) while evacuating the system through the probes 18, using the second stage steam ejector 62 connected to the probes through conduits 78, 80, and 44 with valve 58 open and valves 52 and 33 closed.

The pressure in this system is increased (D) to a value of about 7 inches of mercury corresponding to a temperature of about 140 F. (E). Utilization of steam which is saturated is ensured by introducing water into the steam line downstream of the control valves and upstream of the conditioning chamber. Superheating is thus obviated andfexcess moisture is made available for plating on the tobacco. The flow cycle is then reversed, moisturizing steam being introduced through the probes from the steam source through the conduits 47, 45 and 44, with valve 52 open and valves 58 and 33 closed, and vacuum being applied to the chamber 11 by means of the steam ejector or 62 (G). The pressure reducing valve 48 and the low pressure steam accumulator 50 provide means for reducing the temperature and the pressure of steam entering through the probes and obviate searing or burning of the tobacco contained in the bales or hogsheads. During the reversal, there is an inflection (EF) in the pressure and temperature versus time curve. This discontinuity or shift causes pulsing within and flufilng of the tobacco contained in the hogsheads enhancing moisture penetration and greatly minimizing any likelihood of cold spots. During the flow reversal G or any subsequent flow reversal the equilibrium pressure within the system may increase or may decrease, with corresponding increases or decreases in temperature, the particular values of these parameters depending upon the comparative effectiveness or overall net result of the concurrent evacuation and the steam introduction operations.

In a second flow reversal (J), steam is again introduced into the chamber while evacuating through the probes to bring the system up to a temperature of about 160 F. and to a corresponding pressure of about 10 inches of mercury. A second inflection (HI) occurs in the flow plot (FIGURE 5), pulsing the packed mass to loosen the pack and to fluff the tobacco. The relative direction of steam flow into the system is indicated by arrows in FIGURE 5. In the preferred cycle illustrated, the

160 F. temperature is held for about one minute (KM) and the system is then re-evacuated (N) to a pressure of about 2 inches of mercury corresponding to a temperature of about F. Finally, the system pressure is increased to about 5 inches of mercury and the temperature is raised to about F. (Q). After a holding period (R) of about 2 minutes, the vacuum is broken (5) returning the chamber to atmospheric pressure and creasing values.

in! S) completing the cycle. The overall cycle requires about 22 minutes. In the interest of shortening the conditioning time one skilled in the art may readily modify the steps of the cycle to complete the treatment within about 18 minutes, or even less. The grade, type, and the original condition or state of the tobacco will be an important consideration when scheduling any preferred cycle. v

. The novel methods of tobacco conditioning which are the essence of the present invention, will be described with reference to the drawings. Tobacco contained in hogsheads 13 or barrels is loaded onto wheeled trucks 14 positioned on the trackway 16 and the trucks are moved into the conditioning chamber to predetermined positions such that the vertical axes of the hogsheads are substantially in alignment with the vertical paths of travel of the probes 13. The probes 18 are forced into the tobacco to bring the points 37 to a position adjacent the bottom of the hogsheads 13.. With the door 12 to the chamber sealed, the conditioning or treatment cycle may be initiated. 1

Basically, the method of the invention contemplates a processing cycle including the following steps. The chamber containing the hogshead-packed tobacco is evacuated. The evacuation is to a relatively high degree so that the pressure in the system is below the equilibrium vapor pressure of water in the chamber so that the moisture boils off and non-condensible gases are removed. The initial rate of evacuation is not critical but important economies are achieved through shortened time cycles. In a typical cycle, the initial evacuation requires about 6 to about minutes. Chamber volumes and equipment considerations will control, but rapid evacuation is preferred. With substantially all of the air and other gases removedfrom the chamber and the system pressure in the range of from about 0.15 inch to about 1.0 inch of mercury, and preferably at about 0.2 inch, the initial moisturization is carried out. Steam is introduced into the chamber while vacuum is impressed upon the probes in the tobacco. Water is added to the steam as a spray to ensure saturation and to preclude superheating. During this steaming step the pressure in the system is gradually increased and the temperature within the chamber rises. In a preferred cycling process, the pressure is increased to from about 3 to about 8 inches of mercury and the temperature rises to a corresponding value of from about 115 F. to about 152 F. The flow" of steam through the system is then reversed by evacuating through the chamber and introducing steam directly through the probes, care being exercised to avoid burning the tobacco. During the reversal or the switching of the direction of steam flow through the tobacco, the pressure in the ambient system decreases slightly before proceeding along its path of generally in- Alternatively, the system may be subjected to a generally decreasing pressure after the first steam treatment.

The reversal of flow, which is preferably relatively abrupt, caused physical pehnomena such as pulsings which have several important effects upon the packaged tobacco and upon the completeness of air removal from and steam penetration into and upon uniform permeation of the product treated. That is, the physical agitation or disturbance is conducive to and promotes the formation of new and an increased number of flow paths through the tobacco and tends to minimize channeling. The number of cold spots is greatly reduced and, in most cases, cold spots are practically eliminated. A more uniform ultimate product is obtained and processing losses atributable to powdering are obviated. Since the efiect-iveness of the reverse flow technique of the invention is enhanced upon repetition of the steps described, it is preferred to include in the process cycle at least two flow reversals or flow reversal stages.

The pressure in the system is ultimately increased and the temperature rises as the steam flows into the mass through the probes. Concurrently, the system is evacuated from the chamber itself so that steam flow is in a direction from the inside of the tobacco bale outward. Finally a pressure of about 6 to about 15 inches of mercury corresponding to a temperature of about 140 to about 180 F. is reached. This ultimate temperature and pressure may be reached utilizing only one flow reversal, as described in this example, although, as pointed out, a cycle having two or more reversals is preferred. The highest temperature reached is not critical, but it is desirable in the processing of the tobacco to reach a temperature at which insect destruction is assured. Tests carried out indicate that an expected temperature-time relationship exists. For example, kill or destruction of egg, larva, pupa, and adult moths, beetles, and other insects is achieved in about 1 minute at 170 F., and in about 3 minutes at 150 F. It may be expected that longer times at somewhat lower temperatures may be effective. At still more elevated temperatures shorter times will suffice. Again, in the interest of reducing the processing time, the generally higher temperatures are preferred. However, other obvious considerations, including possible deleterious effects upon the tobacco, dictate against temperatures which are too high.

After a holding period of from about /i to about 3 minutes at the elevated temperature, the system is reevacuated. It is obvious that the holding period is not essential to the efficacy of the process. Moreover, the more slowly the elevated temperature is approached, the less important the holding period becomes. At the same time, the higher the ultimate peak temperature, the less is the need for the holding period-at least for effective destruction of living organisms. In the re-evacuation step it is not necessary to achieve the high degree of evacuation of the initial treatment step. Re-evacuation is preferably from the chamber until a pressure of about 2 inches of mercury and a temperature of about F. are reached. The re-evacuation of the chamber may be carried out while concurrently introducing steam into the system through the probes. Again the final temperature to be reached may be any desired value but is preferably in the range of from about F. to about 145 F. corresponding to a pressure in the range of from about 4 to about 7 inches of mercury.

Appreciable fluffing of the tobacco is achieved during the re-evacuation step. In the final steps of the cycle, steam is introduced into the chamber While evacuat ing through the probe to pass steam inward into the tobacco. A suitable ultimate steam pressure is about 5 inches of mercury, corresponding to a temperature of about 135 F. In a preferred procedure, the system is subjected to a holding period of from about /2 to about 3 minutes at this temperature and pressure to ensure that equilibrium is achieved throughout the contents of the hogshead. Again, the more slowly the final temperature is approached, the shorter is the required holding period. It may, if preferred, be eliminated completely. The final step is to break the vacuum, opening the system to the atmosphere to return the system to ambient temperature and pressure.

The novel arrangement of the structural elements of the apparatus has been described with reference to the new methods and processing procedures of the invention. It may be desired, however, to use the equipment in carrying out more conventional processing cycles not calling for use of probes. Under such circumstances a preferred procedure is to withdraw the probe 18 upwardly through the ceiling opening so that substantialy the entire probe shaft is outside of the vacuum chamber 11. As illustrated in FIGURE 6 a stub pipe section 132 coaxial with the probe shaft is welded or otherwise connected at the ceiling 21 and extends downwardly into the chamber. The pipe section 132 is threaded at its lower end 134 and a cooperating threaded cap 136 is provided to seal the lower or depending end of the pipe section. Thus, with the shaft of the probe retracted to clear the lower end of the downwardly extending pipe and the sealing cap 136 afiixed in position, the chamber may be used in carrying out procedures not involving use of the probes.

Throughout the description and in the specific examples, the invention has for the most part been explained with reference to the treatment or conditioning of tobacco. However, the utility of the methods and of the apparatus disclosed and claimed is not to be construed as limited or restricted in any way to any particular product or group of products. The inventive concept embraces all materials which may advantageously be processed or treated in accordance with the processes and techniques of the invention. The bulk product which is treated in the chamber of the conditioning apparatus may be in any gross physical shape or packaged form including but not limited to bales and hogsheads. Throughout the specification and in the claims the terms bales and/or hogsheads are used not in any limiting sense but as equivalents and one term is intended to include the other.

While disclosures of preferred embodiments of the apparatus and of preferred methods of the invention have been provided, it will be apparent that numerous modifications and variations thereof may be made without departing from underlying principles of the invention. It is, therefore, desired by the following claims to include within the scope of the invent-ion all such variations and modifications by which substantially the results of this invention may be obtained through the use of substantially the same or equivalent means.

What is claimed is: 1. Apparatus for treating a bulk product such as tobacco to adjust the moisture content thereof to provide a uniformly humidified product, said apparatus comprising:

a vacuum chamber adapted to receive tobacco thereinto and for removal of tobacco therefrom;

vacuum producing means for removal of vapor and non-condensibles from said chamber and from said tobacco contained therein,

said vacuum producing means comprising first and second steam ejectors, and condenser means for condensing steam discharged through one of said steam ejectors;

conduit means for introducing steam directly into said vacuum chamber;

probe means for introducing steam directly into said tobacco contained in said chamber;

duct means for direct evacuation of said chamber and conduit means for evacuation of said chamber indirectly through said tobacco contained therein; and means for selectively directing and controlling parts of steam introduction into said chamber and into said tobacco and paths of evacuation of said chamber and of said tobacco contained therein.

2. Apparatus for treating a bulk product such as tobacco to adjust the moisture content thereof to provide a uniformly humidified product, said apparatus comprising:

a vacuum chamber adapted to receive tobacco thereinto and for removal of tobacco therefrom;

vacuum producing means for removal of vapor and non-condensibles from said chamber and from said tobacco contained therein,

said vacuum producing means comprising first and sec ond steam ejectors, and condenser means for condensing steam discharged through one of said steam ejectors;

conduit means for introducing steam directly into said vacuum chamber;

probe means for introducing steam directly into said tobacco contained in said chamber;

said probe means comprising an elongated sharply pointed shaft having a longitudinal bore extending axially therein and a plurality of transverse radial bores communicating with said longitudinal bore, and flexible conduit means connecting said probe to said vacuum producing means and to said means for introducing steam into said tobacco; duct means for direct evacuation of said chamber and conduit means for evacuation of said chamber indirectly. through said tobacco contained therein; andmeans for selectively directing and controlling paths of steam introduction into said chamber and into said tobacco and paths of evacuation of said chamber and of said tobacco contained therein. 3. Apparatus for treating a bulk product such as tobacco to adjust the moisture content thereof to provide a uniformly humidified product, said apparatus comprising:

a vacuum chamber adapted to receive tobacco thereinto and for removal of tobacco therefrom;

vacuum producing means for removal of vapor and non-condensibles from said chamber and from said tobacco contained therein,

said vacuum producing means comprising first and second steam ejectors, and condenser means for condensing steam discharged through one of said steam ejectors;

conduit means for introducing steam directly into said vacuum chamber;

probe means for introducing steam directly into said tobacco contained in said chamber;

probe injection and retraction means for insertion of said probe into said tobacco and for removal of said probe therefrom, said probe injection and retraction means comprising, mechanical drive means for forcibly propelling said probe into tobacco contained in said chamber,

motor means energizing said drive means to insert said probe intosaid tobacco and to withdraw said probe therefrom;

duct means for direct evacuation of said chamber and condut means for evacuation of said chamber indirectly through said tobacco contained therein; and means for selectively directing and controlling paths of steam introduction into said chamber and into said tobacco and paths of evacuation of said chamber and of said tobacco contained therein.

4. Apparatus for treating a bulk product such as tobacco to adjust the moisture content thereof to provide a uniformly humidified product, said apparatus comprising:

a vacuum chamber adapted to receive tobacco thereinto and for removal of tobacco therefrom;

vacuum producing means for removal of vapor and non-condensibles from said chamber and from said tobacco contained therein,

said vacuum producing means comprising first and second steam ejectors, and condenser means for condensing steam discharged through one of said steam ejectors;

conduit means for introducing steam directly into said vacuum chamber;

probe means for introducing steam directly into said tobacco contained in said chamber; duct means for direct evacuation of said chamber and conduit means for evacuation of said chamber indirectly through said tobacco contained therein;

and means for selectively directing and controlling paths of steam introduction into said chamber and into said tobacco and paths of evacuation of said chamber and of said tobacco contained therein,

said directing and controlling means including control valve means to supply saturated steam to said chamber and to impress vacuum upon said chamber,

and sequence conrtoller means connected to said valve means to evacuate said chamber through first evacuation path, to supply saturated steam to said chamber, through a first steam introduction path, to discontinue said steam introduction through said first path, to introduce steam into said chamber through a second steam introduction path, and to evacuate said chamber through a second evacuation path in selected predetermined sequential steps. 5. Apparatus for treating a bulk product such as tobacco to adjust the moisture content thereof to provide a uniformly humidified product, said apparatus comprismg:

a vacuum chamber adapted to receive tobacco thereinto and for removal of tobacco therefrom;

vacuum producing means for removal of vapor and non-condensibles from said chamber and from said tobacco contained therein,

said'vacuum producing means comprising first and second steam ejectors, and condenser means for condensing steam discharged through one of said steam ejectors;

conduit means for introducing steam directly into said vacuum chamber;

probe means for introducing steam directly into said tobacco contained in said chamber;

said probe means comprising an elongated sharply pointed shaft having a longitudinal bore extending axially therein and a plurality of transverse radial bores communicating with said longitudinal bore,

and flexible conduit means connecting said probe to I said vacuum producing means and to said means for introducing steam into said tobacco;

probe injection and retraction means for insertion of said probe into said tobacco and for removal of said probe therefrom, said probe injection and retraction means comprising mechanical drive means for forcibly propelling said probe into tobacco contained in said chamber, motor means energizing said drive means to insert said probe into said tobacco and to withdraw said probe therefrom;

duct means for direct evacuation of said chamber and conduit means for evacuation of said chamber indirectly through said tobacco contained therein;

and means for selectively directing and controlling paths of steam introduction into said chamber and into said tobacco and paths of evacuation of said chamber and of said tobacco contained therein. 6. Apparatus for treating a bulk product such as tobacco to adjust the moisture content thereof to provide a uniformly humidified product, said apparatus comprising:

a vacuum chamber adapted to receive tobacco thereinto and for removal of tobacco therefrom;

vacuum producing means for removal of vapor and non-condensibles from said chamber and from said tobacco contained therein,

said vacuum producing means comprising first and second steam ejectors, and condenser means for condensing steam discharged through one of said steam ejectors;

conduit means for introducing steam directly into said vacuum chamber;

probe means for introducing steam directly into said tobacco contained in said chamber;

said probe means comprising an elongated sharply pointed shaft having a longitudinal bore extending axially therein and a plurality of transverse radial bores communicating with said longitudinal bore,

and flexible conduit means connecting said probe to said vacuum producing means and to said means for introducing steam into said tobacco;

probe injection and retraction means for insertion of said probe into said tobacco and for removal of said probe therefrom, said probe injection and retraction means comprising mechanical drive means for forcibly propelling said probe into tobacco contained in said chamber,

10 motor means energizing said drive means to insert said probe into said tobacco and to withdraw said probe therefrom; said directing and controlling means including control valve means to supply saturated steam to said chamher and to impress vacuum upon said chamber,

and sequence controller means connected to said valve means to evacuate said chamber through a first evacuation path, to supply saturated steam to said chamber, through a first steam introduction path, to discontinue said steam introduction through said first path, to introduce steam into said chamber through a second steam introduction path, and to evacuate said chamber through a second evacuation path in selected predetermined sequential steps.

7. The method of conditioning tobacco contained in a bale or hogshead in a vacuum chamber to provid a uniformly humidified product and comprising the steps of evacuating said chamber to remove substantially all of the air contained therein, introducing steam into said chamber to penetrate said tobacco from outer surfaces of said bale inwardly,

evacuating through a probe inserted into said bale to facilitate drawing steam into said tobacco through outer surfaces thereof, and

introducing steam into said tobacco through said probe to reverse steam flow through said tobacco.

8. The method of conditioning tobacco contained in a bale or hogshead in a vacuum chamber to provide a uniformly humidified product and comprising the steps of evacuating said chamber to remove substantially all of the air contained therein, introducing steam into said chamber to penetrat said tobacco from outer surfaces of said bale inwardly,

evacuating through a probe inserted into said bale to facilitate drawing steam into said tobacco through outer surfaces thereof, introducing steam into said tobacco through said probe to reverse steam flow through said tobacco, and

evacuating through said chamber to facilitate said flow of steam through said tobacco from interior areas of said bale outwardly.

9. The method of conditioning and humidifying tobacco or other materials contained in a bulk package in a vacuum chamber and comprising the steps of evacuating said chamber to remove substantially all of the air therefrom, alternately introducing steam into said chamber to penetrate said material from the outside thereof inwardly, and introducing steam into a probe inserted into said material to pass steam into said material from the interior thereof outwardly to reverse the flow of steam through said material during conditioning thereof while maintaining said chamber at less than atmospheric pressure to provide thereby a uniformly humidified product.

10. The method of humidifying a product in a bulk package to increase moisture content therein to provide a uniformly moisturized product and comprising:

subjecting the product to a sub-atmospheric pressure in in the range of from about 1.0 inch to about 0.15 inch of mercury absolute, introducing steam directly into a chamber containing said product to pass said steam into said product to penetrate into said bulk package from outer surfaces thereof inward, terminating the said introduction of steam directly into into said chamber and introducing steam into said product through probe means extending into said bulk package to reverse the fiow of steam through said product, bringing said product to a predetermined temperature and moisture content, and opening said chamber to atmosphere to bring said product to atmospheric pressure and temperature. 11. The method of conditioning tobacco contained in a bale or hogshead in a vacuum chamber to provide a 1 1 uniformly humidified product and comprising the steps of initially evacuating said chamebr to remove substantially all of the air contained therein, introducing steam into said chamber to penetrate said tobacco from the outer surface of said bale inwardly,

evacuating said chamebr through a probe inserted into said bale to facilitate drawing steam into said tobacco from the outer surface of said bale inwardly,

introducing steam into said tobacco through said probe,

and

evacuating said chamber to force and to draw steam into said tobacco from the interior of said bale outwardly,

to reverse thereby flow of steam through said tobacco to provide a uniformly humidfied tobacco product.

12. The method of conditioning tobacco contained in a bale or hogshead in a vacuum chamber to provide a uniformly humidified product and comprising the steps of initially evacuating said chamber to remove substantially all of the air contained therein,

introducing steam into said chamber to penetrate said tobacco from the outer surface of said bale inwardly, evacuating said chamber through a probe inserted into said bale to facilitate drawing steam into said tobacco from the outer surface of said bale inwardly, introducing steam into said tobacco through said probe, re-evacuating said chamber to a final pressure greater than that reached in the initial evacuation, introducing steam into said chamber to increase the pressure within said chamber and the temperature of the tobacco contained therein,

terminating said steam introduction into said chamber at a predetermined pressure and temperature,

and breaking the vacuum in said chamber to bring said chamber to atmospheric pressure.

13. The method of conditioning tobacco to provide an homogeneous humidified product having a predetermined moisture content substantially uniformly distributed therethrough and comprising the steps of:

introducing a bale of tobacco into a conditioning chamber;

inserting a steaming and evacuation probe into said bale;

connecting said probe to vacuum source and to a steam supply exteriorly of said conditioning chamber; connecting said conditioning chamber to a vacuum source and to a steam supply;

initially evacuating said conditioning chamber to an absolute pressure in the range of from about 0.15 inch to about 1.0 inch of mercury, introducing steam into said conditioning chamber while evacuating through said probe to provide an over-all increase in moisture and to increase the pressure within said chamber to from about 3 inches to about 8 inches of mercury and the temperature to from about 115 F. to about 152 F.

terminating inflow of steam into said chamber and initiating steam flow through said probe and into said bale and evacuating through said chamber to reverse the direction of steam flow throughout said bale of tobacco, evacuating through said probe and concurrently introducing steam into said chamber to reverse the flow of steam within said bale again and to increase the pressure in said chamber to an absolute value in the range of from about 6 inches to about inches of mercury to elevate the temperature within said chamber to a value from about 140 F. to about 180 F.,

maintaining the temperature within said chamber at about 140 F. to about 180 F. for a short finite time time in the range of from about /2 to about 3 minutes,

re-evacuating said chamber to an absolute pressure of about 2 inches of mercury to remove noncondensible gases from said chamber and from said tobacco introducing steam into said chamber to provide a final absolute pressure of from about 4 inches to about 7 inches of mercury,

maintaining the pressure in said chamber a short finite time at about 4 inches to about 7 inches of mercury, and breaking the vacuum in said chamber to complete the conditioning process. 14. The method of conditioning tobacco to provide a substantially uniform distribution of moisture therethrough, said method comprising the steps of evacuating a system comprising a chamber containing a bale of tobacco to remove all but a small amount of ambient gases therefrom,

introducing steam into said bale through exterior surfaces thereof inwardly while evacuating said system through a foraminous probe inserted into said bale,

and introducing steam into said probe to enter said bale and to travel through said bale from the interior thereof outwardly While evacuating said system through said chamber to reversethe flow of steam through said tobacco during conditioning thereof to provide a humidified product having moisture distributed substantially uniformly therethrough.

15. The method of conditioning tobacco to provide a substantially uniform distribution of moisture therethrough, said method comprising the steps of evacuating a system comprising a chamber containing a bale of tobacco to remove all but a small amount of ambient gases therefrom,

introducing steam into said bale through exterior surfaces thereof inwardly while evacuating said system through a foraminous probe inserted into said bale,

introducing steam into said probe to enter said bale and to travel through said bale from the interior thereof outwardly while evacuating said system through said chamber to reverse the flow of steam through said tobacco during conditioning thereof to provide a humidified product having moisture distributed substantially uniformly therethrough, re-evaeuating said chamber to an absolute pressure greater than that reached in the initial evacuation;

introducing steam into said chamber to increase the pressure in said chamber to a value in the range of 4 to 7 inches of mercury and to raise the temperature of said tobacco to a temperature in the range of from about F. to about F.;

and introducing air into said chamber to bring the pressure of said chamber to atmospheric.

16. The apparatus of claim 2 wherein said chamber has a ceiling port defining an opening through which said probe means is insertable to extend into said chamber and to project into tobacco contained therein,

and further comprising port capping means for sealing. said port and effective to preclude flow of fluid through said port and into and from said chamber upon retraction of said probe means upwardly of said chamber.

1'7. The apparatus of claim 16 wherein said port sealing means comprises an elongated closed end sleeve and coupling means for connecting said sleeve at said ceiling port to seal said port to ambient atmosphere.

References Cited by the Examiner UNITED STATES PATENTS 2,900,986 8/1959 Pietruska 131-l34 2,997,046 8/1961 Doyle 131l33 3,124,142 3/1964 Philbrick et al. 131-133 SAMUEL KOREN, Primary Examiner.

MELVIN D. REIN, Examiner. 

1. APPARATUS FOR TREATING A BULK PRODUCT SUCH AS TOBACCO TO ADJUST THE MOISTURE CONTENT THEREOF TO PROVIDE A UNIFORMLY HUMIDIFIED PRODUCT, SAID APPARATUS COMPRISING: A VACUUM CHAMBER ADAPTED TO RECEIVE TOBACCO THEREINTO AND FOR REMOVAL OF TOBACCO THEREFROM; VACUUM PRODUCING MEANS FOR REMVOAL OF VAPOR AND NON-CONDENSIBLES FROM SAID CHAMBER AND FROM SAID TOBACCO CONTAINING THEREIN, SAID VACUUM PRODUCING MEANS COMPRISING FIRST AND SECOND STREAM EJECTORS, AND CONDENSER MEANS FOR CONDENSING STEAM DISCHARGED THROUGH ONE OF SAID STEAM EJECTORS; CONDUIT MEANS FOR INTRODUCING STEAM DIRECTLY INTO SAID VACUUM CHAMBER; PROBE MEANS FOR INTRODUCING STEAM DIRECTLY INTO SAID TOBACCO CONTAINED IN SAID CHAMBER; DUCT MEANS FOR DIRECT EVACUATION OF SAID CHAMBER AND CONDUIT MEANS FOR EVACUATION OF SAID CHAMBER INDIRECTLY THROUGH SAID TOBACCO CONTAINED THEREIN; AND MEANS FOR SELECTIVELY DIRECTING AND CONTROLLING PATHS OF STEAM INTRODUCTION INTO SAID CHAMBER AND INTO SAID TOBACCO AND PATHS OF EVACUATION OF SAID CHAMBER AND OF SAID TOBACCO CONTAINED THEREIN. 